Method of filling and sealing containers



Aug. 26, 147.

s. s. JAcoBs- Er A1. 2,426,555 ETHOD OF FILLING `AND SEALING CONTAINERSFiled June l0, v1941 2 Sheets-Sheet l AT-roerlaEYs Aug. 26, 1947. s. s.JACOBS Er AL IETHOD 0F FILLING AND SEALING CHTAINERS vFiled June 1o,1941 2 sheets-sheet' 2 Patented Aug. 26, 1947 METHODOF FILLING'ANDSEALING CONTAINERS Samuel S. Jacobs, San Mateo, and Stellan Birkland,San Francisco, Calif., assig'nors to American Can Company, New York,N..Y., a corporation of New Jersey Application June 10, 1941, Serial No.397,476

2 Claims. (Cl. 22S- 75) The present invention relates to a vmethod ofvacuum filling and sealing containers or cans and has particularreference to vacuum filling and vacuum sealing containers underrespectively different degrees of vacuum in the same overall vacuumregion or chamber.

In the filling and closing of cans under a vacuum it usually isdesirable to obtain the highy est possible degree of vacuum in the canduring the filling operation. However, when this same can is closed andsealed as in a double seaming machine, it is desirable to reduce thevacuum in the can in order to preventl boiling over of the contentsduring the sealing operation. Such conditions usually require theseparatey drawing of the desired degrees of vaccum on the can for eachoperation, with the result that the time and cost of drawing thesevacuums are usually great.

The instant invention contemplates overcoming these di'iculties byproviding a method of vacuum filling and sealing such cans in two stagesof vacuumization, both effected in the same vacuum chamber, the chamberbeing maintained at the proper sealing vacuum and the can while in thechamber being separately exhausted to a higher degree of -vacuum for thefilling operation.

An object, therefore, of the invention is the provision of a method ofvacuum filling and seal'-V ing cans wherein the can is introduced into aregion maintained at a constant relatively low vacuum suitable forsealing and while in this region is separately vacuumized to a higher*de' gree for lling so that the proper high vacuum will obtain in the canduring the filling operation and also the desired low vacuum during theclosing operation while maintaining the canin a single vacuumizedregion.

Another object is the provision of such' a method of filling and sealingcans wherein the vacuumization of the cans can be eiectedwhile the canside walls remain unsupported.

Numerous other objects and advantages of the invention will be apparentas it is better understood from the following description, which,

taken in connection with the accompanying drawingsdiscloses a preferredembodiment thereof.

Referring to the drawings:

, Figure 1 is a horizontal section of apparatus for carrying out thesteps embodying the instant method invention, With parts broken away;

Fig. 2 is anenlarged sectional detail of a cover feed device, takensubstantially along the line 2-2 in Fig. 1, with parts broken away; 4 v

Fig. 3 is a perspective view of a valve part of the cover feed shown inFig. 2, with a cover i'n place for feeding; and l Fig. 4 is a compositelongitudinal section taken substantially along the broken line 4-4 inFig. 1, with parts broken away.

As a preferred embodiment of the instant method invention, empty cans Aare introduced into a chamber B which constitutes an overall vacuumchamber or region and which is maintained under a constant relativelylow vacuum. The product being filled determines what low vacuum is used,some products like peaches hav.

ing very ylittle vacuum on this low vacuum stage. As an example of lowvacuum for products which are best canned in an initial higher vacuumthan that used for peaches 22 inches may be mentioned. An empty canreceived into such a vacuumized region is accordingly exhausted of its'airk to the extent of the vacuum in the region.

The interior of such a received and low vacuumized can thereupon is'closed off and a relatively high vacuum is drawn on the can.`

Approximately 29 inches may be given as aflgure -for the can vacuumizedat 22 inches. 'Ihus the vacuum in the can need be increased only seveninches of vacuum and since the difference between the two pressures isso small the can side walls need no support against collapse. Whileunder -this high vacuum the can is filled with its contents. Afterfilling, the can isuncovered and it is thus again subjected to the lowvacuum condition of the chamber. A permanent cover is then positioned onthe filled can and is sealed in place. Sealing of the can is followed byits discharge from the chamber to lany suitable place of deposit.

Such a method of filling and sealing cans under such a two-stagevacuumizing process makes it possible toiill the can under the highestvacuum obtainable and to immediately seal 'the can while in the samechamber at a properly reduced vacruum which prevents boiling over of.the contents of the can. The proper head space in the can is thusmaintained and the time and cost of pulling separate vacuums on the canand in different positions are reduced. i

The drawings illustrate one form of apparatus for carrying out thesemethod steps. In such anv apparatus the chamber B is enclosed by acasing lI(Figs. 1 and 4) which constitutes the main frame of theapparatus. The empty cans Ato be filled and sealed are received inspaced and .timed order on acontinuously moving endless ,belges whichoperates over a pulley i3 carried on @shaft I4 journaled in'bearings I5formed on .an egten--Y sion I6 of the casing Il. Guide rails I8 disposedadjacent the belt, keep the moving cans in line on the belt.

The feed-in belt I2 terminates adjacent a constantly rotating entrancevalve 2| which is located in an opening 22 adjacent a valve seat 23iormedl in the casing I I. This valve seals oil the opening in theycasing while permitting cans A to be passed therethrough into thechamber B. The valve is mounted on a vertical shaft 24 which isjournaled in bearings 25 formed in the casing. The shaft is rotatedv inany suitable manner in time with the other moving parts of theapparatus. The valve is formed with spaced pockets 2li.V

which are carried by the rotating valve into the path of the cans on thebelt I2. Thus the transfer of the cans individually into the chamber Bis effected. l

As hereinbefore mentioned, the chamber B is maintained under a vacuum ofapproximately 20 22 inches. This vacuum is drawn from any suitablesource by way of a pipe 21 (Fig. 4). .The chamber end of this pipe isthreaded into the bottom of the casing I.4

A can A introduced into the chamber B is received in a rotating canlling mechanism generally indicated by the numeral 3|. By Way ofexample,the cans A are shown as being filled with liquid contents and forpurposes of illustration the drawings illustrate a liquid iillingmechanism of the character disclosed in United States Patent 2,124,581,issued July 26, 1938, to R. Luthi on Can lling machine. l

Such a lling mechanism includes a rotatable turret 32 which is mountedon a stationary hollow post 33. The turret is formed with a plurality ofpockets 34 spacede around its periphery. Below each pocket there is a,lifter plate 35 .which is vertically movable and which receives andsupports an empty can A which comes from the entrance valve 2| whentheplate passes adjacent the valve. Above each turret pocket there is afilling head 3B having a rotatable valve 39. These heads are secured toa tank or reservoir 4I in which the liquid to be lled into the cans isretained. The tank is carried on the turret and rotates with the turret.

Hence when a can A is received in a pocket 34 of the turret it restsupon a lifter plate 35 'and the latter carries the can around with theturret in a circular path of travel. A curved guide rail 42 disposedadjacent the periphery of the turret holds the can in its pocket. Duringthis travel vthe lifter plate raises the can into engagement with theiilling head directly above and this closes off the interior of the canfrom reduced atmosphere of the chamber B.

While in this position the interior of the can is further vacuumized tothe higher vacuum of 29 inches hereinbefore mentioned. This is broughtabout by a turning 'of the valve 39 which turning may be effected in anysuitable manner such as that disclosed in the above Luthi patent.

The valve 39 is formed with suitable ports whichare brought intoregister with other ports in the ill-ling head 38. One of these fillinghead ports communicates with a passageway 45 (Fig. 4) in the bottom wallof the tank and this passageway communicates with a b'ore `46 formed inthe stationary port 33. This bore leads from any suitable source of thehigher vacuum. Hence when the valve 39 is in the proper position 'theinterior of the can is in communication with the source of the highervacuum and the can is accordingly vacuumized to correspond with thehigher vacuum.

Immediately after such a separate vacuumizing of the interior of the canA, the latter is filled with its contents. This is effected by anotherturning of the valve 33 which brings certain ports therein into registerwith ports in the lling head 38 which communicates with a passageway 41which leads from the interior oi! the tank 4|. When the valve is in thisposition, liquid from the tank flows through the passageway 41, valve39, and lling head 38 into the can until the latter is illled.

When the can is filled the valve 33 is again turned to a position whichcuts ofl the ports in the filling head and brings the interior of thecan into communication again with the lower vacuum pressure in thechamber B. The lifter plate 35 thereupon moves down 'and carries thelled can down to its original level during which time it remains exposedto the low vacuum within the chamber B.

Liquid drained out of the tank 4| is replenshied by way of an inlet pipe5| which leads from any suitable source of supply of the liquid. Thispipe extends down through a stumng box 52 in the top of the casing andthe inner end of the pipe is secured to a cover 53 on the tank 4I. Y

A filled can A is removed from the turret 32 of the filling mechanism 3|by way of a star wheel 55 (Fig. l) which is disposed adjacent theperiphery of the lling turret 32. This star wheel is mounted on avertical shaft 5B in the casing and may be rotated in any suitablemanner in time with the other moving parts of the apparatus. The starwheel propels the cans along a reversed curved path of travel andpositionsthem into spaced pockets 8| of a rotating seaming heads foreachl turret pocket and the heads are rotated in any suitable manner.

A can A thus received in the closing mechanism 64 is carried around acircular path of disposed adjacent the periphery of the turret retainsthe cans in their pockets. While the cans are moving along this path oftravel can'ends or covers C are deposited on top of them.

The can ends C preferably are introduced into the low vacuum chamber Bby way of a valve 1| (Figs. 1 and 2) disposed adjacent an opening 12 inthe casing The entering can ends are fed along a runway 13 on the casingby a reciprocating feed bar 14 which slides -in a groove 15 formed inthe runway. Feed dogs 16 in the feed bar advance the can ends throughthe opening 12 in the casing and place them in the valve 1|. i

The valve 1|-s1ides up and down in a housing 1s mated inside the vacuumchamber B and is formed on the casing adjacent the opening 12-` Adjacentthe bottom, the housing is formed with a slot 19. When the valve is inits upper- .most position it aligns with the opening 12 for A curvedguide rail 89 belt conveyor.

end, the valve moves down in its housing into alignment with the slot 19while still blocking off two linger star wheel 8l mounted on a shaft 82sweeps the can end C from the! valve 1I and propels it along a curvedrunway 83.v This runway guides the can end toward a moving can A rin theturret 62 and at the terminal end of the runway the can end slides intoposition on the top of the can.`

As soon as a can receivesits cover or end -it is lifted into itscorresponding closing head 61 and the cover is thereupon permanentlysecured to the can. Lifting of the can is eifected by the lifter pad 68on which it rests and this lifting and the closing of the can is donewhile it is carried around its forward travel'by the rotating turret 62.

At the completion of the can closing operation, the lifter pad 66 movesdown and thus returns the ca n to its original level in time to engageagainst a stationary ejecting rail 85 which ejects the closed can fromthe closing turret 62.. This i rail is secured to the inside of thecasing il and projects inwardly into the path of travel of the cans inthe turret.

The ejected closed can A is received in a pocket 86 of a rotating valve81 disposed in a valve seat 88 formed in the casing II adjacent a candischarge opening 89 therein. The valve is mounted on a vertical shaft9| journaled in bearings 92 in the casing Il and is rotated in anysuitable manner in time with the other moving parts of the apparatus.

The rotating valve 81 carries the closed can out of the vacuum chamber Band brings it adjacent a discharge endless belt conveyor 93 disposedoutside'the casing Il. Fingers 94 pivotally mounted in the valve pushthe closed can,

out of its turret pocket 86 and position it on the The conveyor carriesthe can to any suitable place of deposit and this completes theoperationsof filling'and sealing the can under the desired vacuumconditions.

It is thought that the invention and many of its attendant advantageswill be understood from the foregoing description, and itwill beapparent that various changes may be made in the steps of the processdescribed and" their order of accomplishment without departing ,from thespirit and scope of the invention or sacricing all of its materia]advantages, the process hereinbefore described being merely a. preferredembodiment thereof.

We claim:

1. The method of vacuum filling and vacuum sealing containers underrespectively v'different degrees of vacuum in the same overall vacuumchamber, which comprises the steps of introducing a plurality ofunsealed containers in continuous procession into said chamber wherein asubstantially constant partial vacuum is continuously maintained, whichvacuum is not -appreciably disturbed by said continuous introduction ofcontainers, temporarily sealing from said chamber the interior of each;container thus introduced while its exterior is exposed to said partial'vacuum maintained in said chamber, increasing the vacuum in the interiorof each of said con. tainers, then llingeach container while thecontainer interior is thus temporarily sealed from said chamber, thensubstantially equalizing the vacuum within each container with thatinthe chamber, then hermetically sealingl each container in said chamberwhile under said partial vacuum, and iinally discharging saidhermetically. sealed containers in continuous procession fromsaid-chamber without appreciably disturbing said partial vacuum withinsaid chamber.

2. The method of vacuum iilling and vacuum sealing containers underrespectively different degrecs of vacuum in the same overall vacuumregion wherein a substantially constant vacuum is continuouslymaintained, comprising the steps of successively feeding a plurality ofopen top containers and separate sealing closures into said regionwithout appreciably disturbing the constant vacuum maintained insaid..region, temporar-ily sealing -said open top containers against avacuum and filling head located in said region, thereby temporarilyseparating the interior of the containers from said region, drawing avacuum on the interior of each of said temporarily sealed containers ofa degree diierent from the vacuum prevailing on the exterior of saidcontainer in said region but within limits of pres,-

sure difference which protect the container walls against injury, thenfilling the containers thus temporarilysealed from said region, breakingsaid temporary seals and successively transferring said containers to anhermetic nal sealing station also located in said region, then securingsaid sealing closures hermetically to said containers and iinallydischarging said filled and hermetically sealed containers from saidregion without appreciably disturbing the constant vacuum maintained insaid region.

SAMUEL S. JACOBS.

STELLAN BIRKLAND.

REFERENCES CITED The following references are of record in the

